chunkd thread work

chunkd thread work

[Jeff Garzik]

I removed libevent support from chunkd, because I felt it was blocking 
the multi-threading of chunkd to an unfortunate degree.  libevent does 
not provide any protection for multiple threads adding and removing 
themselves to a single poll-set.

Multi-threading chunkd should enable us to reach our full I/O throughput 
potential through parallelization.  It will also enable useful 
administrative tasks such as background checksum verification.

	Jeff




commit 47a916242eb795b27ca86cb68a25135a14741b5f
Author: Jeff Garzik <jeff@garzik.org>
Date:   Sun Nov 1 23:11:18 2009 -0500

     chunkd: drop libevent support, due to lack of thread-friendliness

     libevent does not support a single poll-set being manipulated
     simultaneously by multiple threads, so it is replaced with a
     poll(2)-based mechanism highly similar to cld's.

     An epoll mechanism would be a logical next-step.

     Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

commit 441eb192ef5d68e6d563f045a3c061d9bc403684
Author: Jeff Garzik <jeff@garzik.org>
Date:   Sun Nov 1 20:39:09 2009 -0500

     chunkd: add cli_wr_set_poll() to isolate libevent usage

     Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

Re: chunkd thread work

[Pete Zaitcev]

On Sun, 01 Nov 2009 23:21:55 -0500, Jeff Garzik <jeff@garzik.org> wrote:

> Multi-threading chunkd should enable us to reach our full I/O throughput 
> potential through parallelization.  It will also enable useful 
> administrative tasks such as background checksum verification.

I'll get to it Real Soon Now.

-- Pete